The U.S. Energy Information Administration conducted a survey of commercial buildings in the U.S. in 2012 culminating in a 2015 report. The report states that there are 5.6M buildings containing 87B square feet of space. The federal government owns 775,000 buildings and estimates that 55% of the $23B annual operating cost goes to maintenance.
Owners of such facilities work to maximize the value of dollars spent on maintenance. Periodic and special Facility Condition Assessments (FCA) provide owners with information with which to anticipate and plan routine maintenance and to spot special needs as they develop. Assessments are typically conducted by facilities engineers, architects, consulting engineers, and senior technicians by studying record drawings, making visual observations of the many elements of the facility, and reviewing photographs documenting past and present conditions.
Many elements of a building that bear on its condition are in elevated places that are difficult or risky to access. For instance, air handling equipment in a tall warehouse may be located just below or within the roof trusses and the roofs may be sloped and several stories high making access dangerous. Conventional means of accessing such locations, has been by ladder, scissor-lift or bucket-lift, or perhaps from an adjacent higher building. More recently, some consultants have attempted to use drones to inspect roofs.
Many government facilities have very strict rules prohibiting the use of cell phones/camera phones and wireless devices. This can negatively impact the availability and quality of photographs or even visual observations.
There are several problems with existing solutions, such as personal elevation, drones, pole mounted devices, and others. Any solution that involves placing a worker more than several feet above the ground brings added risks of falling and of dropping items. Many FCA engagements involve sending teams of engineers and architects to conduct the work at installations in various locations. While some facilities may own and maintain very tall ladders and/or stable lifts and permit their use for FCAs, many do not. Availability of the necessary rental equipment may be problematical and such equipment is not portable, often varies significantly from one location to the next and typically requires skill and added safety measures. The dangers include falling from or dropping tools from heights, damaging the sides, windows, and roofs of buildings by ladders leaning at the wrong point or buckets bumping (crashing), and increased potential for electrical shock.
Drone usage has met with mixed results due to airspace restrictions, unpredictable wind currents near structures, limited carrying capacity, limited flight time, liability concerns, public acceptance, and the complexity of safe, controlled flight.
Assessment teams have used pole mounted cameras—a selfie stick, a painter's pole, and a photographer's monopod, however, the practical height limitation seems to be about 25 to 30 feet. The maneuverability of poles beyond about 25′ proves very cumbersome and demands both hands and significant upper body strength; this results in the need for an additional person to view and operate the camera or other optics. Stability quickly becomes problematical with even a small device and can increase substantially with even a light wind.
Without the ability to get physically close to an element for inspection/assessment, visibility and clarity are problematical. If an element can be seen from the ground, high resolution binoculars or camera can be used to gather information. However, optical capability comes with added weight (increasing torque), thus reducing the practical height at which it can be used.